1. 定义一个矩形类，拥有属性：长、宽 拥有方法：求周长、求面积

   class Rect:
       def __init__(self, long1=10, width1=20):
           self.long = long1
           self.width = width1
   
       def area(self):
           print(f'面积：{self.long * self.width}')
   
       def perimeter(self):
           print(f'周长：{(self.width +self.long)*2 }')
   r1 = Rect(20,30)
   r2 = Rect(10,30)
   r3 = Rect()
   r2.area()
   r1.perimeter()
   r3.area()
   

2. 定义一个二维点类，拥有属性：x坐标、y坐标 拥有方法：求当前点到另外一个点的距离

   class Points:
       def __init__(self, x1=0, y1=0):
           self.x = x1
           self.y = y1
   
       def distance(self, point):
           long = ((self.x-point.x)**2 + (self.y-point.y)**2)**0.5
           return long
   p1 = Points(60, 10)
   p2 = Points(10, 20)
   print(f'两点距离：{p1.distance(p2)}')
   

3. 定义一个圆类，拥有属性：半径、圆心 拥有方法：求圆的周长和面积、判断当前圆和另一个圆是否外切

   class Circle:
       def __init__(self, mid_point_x1=0, mid_point_y1=0, r_=1):
           self.mid_point_x = mid_point_x1
           self.mid_point_y = mid_point_y1
           self.r = r_
   
       def area(self):
           print(f'面积：{3.14*self.r**2}')
   
       def perimeter(self):
           print(f'周长：{2*3.14*self.r}')
           
       def qie(self, point):
           mid_distence = ((self.x-point.x)**2 + (self.y-point.y)**2)**0.5
           if mid_distence == self.r + point.r:
               return True
           else:
               return False
   

4. 定义一个线段类，拥有属性：起点和终点， 拥有方法：获取线段的长度

   class Line:
       def __init__(self, stx=0, sty=0, endx=0, endy=0):
           self.stx = stx
           self.sty = sty
           self.endx = endx
           self.endy = endy
       def long(self):
           l = ((self.stx - self.endx)**2 + (self.sty - self.endy )**2)**0.5
           return l
   

5. 定义一个狗类和一个人类：

   狗拥有属性：姓名、性别和品种 拥有方法：叫唤

   人类拥有属性：姓名、年龄、狗 拥有方法：遛狗

class Dogs:
    def __init__(self, name1, gender1, type1):
      self.name = name1
      self.gender = gender1
      self.type = type1
      
    def bark(self):
        print('叫唤')

class Person:
    def __init__(self, name, age,dog):
        self.name = name
        self.age = age
        self.dog = dog